The use of E-mails to transmit/receive text information is becoming popular along with the recent widespread use of computers and networking of information.
E-mail can have attached files of various formats in addition to a mail text, i.e., text information. Internet FAX (to be referred to as IFAX hereinafter) is coming into wide use, which transmits/receives an image by attaching, e.g., a TIFF (Tag Image File Format) file.
The IFAX is a technique for inter-device communication. That is, a transmission device reads an image by a scanner, converts it into a TIFF image, and transmits the data to a destination. A reception device decodes the TIFF image from the received data and prints it.
In relation to this technique, Japanese Patent Laid-Open No. 2002-27193 discloses an apparatus for transmitting image data by using an e-mail protocol. This apparatus transmits image data directly to a reception device without intervention of a mail server.
Japanese Patent Laid-Open No. 2003-233558 also discloses an apparatus for transmitting image data by using an e-mail protocol. This apparatus holds, for each destination on an address book, data representing whether to transmit image data directly to a reception device without intervention of a mail server. On the basis of this data, the apparatus directly transmits data to a reception device at a destination that allows direct transmission without intervention of a mail server.
RFC2532 defines the Full Mode standard of IFAX. According to this standard, when a transmission device transmits image data to a reception device, the reception device notifies the transmission device of the reception result using MDN (Message Disposition Notification).
In a system that causes a transmission device to transmit image data to a reception device without intervention of a mail server in accordance with the Full Mode standard, the arrangements disclosed in Japanese Patent Laid-Open Nos. 2002-27193 and 2003-233558 can directly transmit image data from the transmission device to the reception device.
However, the reception device that should transmit the MDN result to the transmission device cannot determine whether the MDN transmission destination permits direct transmission or not.
The reception device always transmits MDN via a mail server which is therefore indispensable.
It is however not easy to install and operate a mail server. A system that is operated in only an environment capable of communication without intervention of a mail server includes, e.g., a system that transmits image data in accordance with an e-mail protocol without building a mail server. In IFAX that transmits a large image file regardless of the presence of a mail server, the load on the mail server poses a problem. Hence, setting is often done while intentionally avoiding use of a mail server.
In a system where a reception device successfully receives e-mail data, analyzes it, and extracts an image, the success of data reception does not always indicate the success of image formation in the reception device based on the data. If a failure such as exhausting of the capacity of the internal data storage device of the reception device halfway through the process occurs, image formation in the reception device fails.
To finally confirm the success of communication, confirmation by MDN is necessary. In an environment where no mail server is installed or set, MDN transmission does not occur. It is therefore impossible to determine whether the reception device have normally received the transmitted e-mail data.